In recent years, a pressure sensor employing spin technology has been proposed. The pressure sensor employing spin technology is a device that measures a pressure using a principle that magnetization directions in a plurality of magnetic layers change relatively due to a pressure changing, whereby a value of electrical resistance of an element changes. Such a pressure sensor has a strain detection element employing spin technology disposed on a membrane formed on a support member; and converts a strain of the membrane caused by the pressure into a resistance change of the strain detection element, thereby detecting the pressure applied to the membrane.
A structure in which such a pressure sensor has a plurality of strain detection elements employing spin technology disposed on one membrane that bends by the pressure, has been proposed. The pressure sensor including these plurality of strain detection elements desirably shows a response in which there is no occurrence of unintended variation in characteristics among the strain detection elements.
In order to achieve an improvement in performance of such a pressure sensor, characteristics of the membrane including a film thickness of the membrane are preferably uniform. However, in a pressure sensor employing a conventional material of the membrane, it has been difficult to render characteristics of the membrane uniform, hence it has not been easy to improve performance of the pressure sensor.